Title: Morphology and anatomy of sylleptic shoots of plum trees (Prunus domestica L.) as influenced by different dates of shoot heading during summer pruning

Authors:Ivan P. Glišić, Dragica Vilotić, Tomo Milošević, Gorica Paunović, Radmila Ilić

Download: PDF

Abstract: This study was conducted during two years under the environmental conditions of ^a~ak (western Serbia) to evaluate the effects of different dates of shoot heading during summer pruning on the intensity of sylleptic shoot formation and the main morphological and anatomical traits of sylleptic shoots in plum cultivar ‘^acanska Rodna’ grafted on Myrobalan rootstock during five and six years after planting. The experiment was established with a spacing of 4 m × 2 m (1,250 trees ha-1). Shoots were headed back to four buds from the base at five different dates to stimulate sylleptic shoot development. The first heading-back date (T1) was 30 days upon the beginning of shoot growth and the remaining ones (T2, T3, T4, and T5) continued at 15-day intervals. At the end of winter dormancy (February), measurements of morphological traits of sylleptic shoots, including length and diameter of sylleptic shoots (cm), node number, node length (cm), and number of vegetative and flowering buds, as well as of anatomical traits, i.e., xylem area width (μm), number of tracheae per mm2 and trachea diameter (μm) were made. Results showed that T4 and T5 were late shoot heading dates (around July 5 and July 20, respectively), given the very poor development of sylleptic shoots until the end of the growing season. Among the remaining three shoot heading dates, T3 (around June 20) was the most favorable as it produced sylleptic shoots of moderate length, i.e., vigour, having a very good ratio of flower buds to vegetative buds, and normal anatomical traits. These results provide new insight into dates and methods of summer pruning of plums grown in a high density planting system aimed at regulating tree vigor and improving cropping potential.

Key words: morphological and anatomical traits, Prunus domestica L., shoot heading, summer pruning, sylleptic shoos

Title: An overview of S-genotype diversity in sweet cherry landraces grown in the central region of the Republic of Serbia

Authors:Slađana Marić, Sanja Radičević, Nebojša Milošević, Ivana Glišić, Milena Đorđević, Bojana Banović Đeri

Download: PDF

Abstract: Identification of the S-genotypes in landraces is a crucial step in the molecular characterization of Serbian autochthonous sweet cherry germplasm. It is also of enormous significance for breeders and growers, as this fruit species exhibits a gametophytic self-incompatibility, controlled by the multi-allelic two genes of the S-locus. The aim of this study was to summarize known information and reveal new data on the S-alleles in 23 sweet cherry landraces originating in the Republic of Serbia. The use of polymerase chain reaction (PCR) with consensus primers for the second intron of SRNase, primers specific for S-RNase and certain SFB alleles, along with DNA fragment analysis using fluorescently labelled forward primers to amplify both the S-RNase first intron and the SFB intron, revealed 10 alleles (S1 to S6, S9, S12, S13 and S22) that generated the following 13 S-genotypes: S1S2 (one landrace), S1S4 (one landrace), S1S5 (one landrace), S2S3 (four landraces), S3S4 (two landraces), S3S5 (two landraces), S3S6 (three landraces), S3S9 (two landraces), S3S12 (two landraces), S4S5 (one landrace), S4S13 (one landrace), S5S22 (one landrace) and S6S9 (two landraces). The most frequent S-allele and S-genotype in this sweet cherry material were S3 and S2S3, with occurrence frequencies of 32.6% and 17.4%, respectively. Based on the obtained results, the sweet cherry landraces were assigned to 12 incompatibility groups and one group of universal donors (‘0’). These results provide important information about their cross-compatibility and the diversity of the S-locus in Serbian sweet cherry germplasm.

Key words: Prunus avium L., autochthonous genotype, S-RNase, SFB, S-haplotype, gametophytic self-incompatibility

Title: VIGOR REDUCTION AND FRUIT TRAITS OF SWEET CHERRY GRAFTED ON ‘OBLAČINSKA’ SOUR CHERRY, EUROPEAN GROUND CHERRY AND MAHALEB SELECTIONS

Authors:Tijana Narandžić, Mirjana Ljubojević, Dragan Milatović, Magdalena Pušić, Milica Grubač

Download: PDF

Abstract: The selection of rootstocks with size-controling effects on scions, combined with the achievement of fruit quality in accordance with market requirements, are of great importance for the establishment of sweet cherry high-density plantations. This study aimed to investigate how 25 rootstock candidates, selected within species Prunus cerasus L., Prunus fruticosa Pall. and Prunus mahaleb L., influence vigor reduction of grafted sweet cherry trees, expressed by trunk crosssectional area (TCSA) reduction, as well as fruit morphological and organoleptic characteristics compared to standard rootstocks. The trial was carried out at the experimental field of the Faculty of Agriculture, the University of Novi Sad, located in Rimski Šančevi, Northern Serbia (45°20’ N; 19°50’ E) at 80 m a.s.l. From the first year after planting, the trees were not pruned. The trial was not irrigated until the seventh growing season, while a minimal amount of pesticides was apllied each year. Plant material included the cultivar ‘Summit’ grafted on 27 rootstock candidates within genus Prunus sp. ‡ 11 selections of P. cerasus L. ecovar. ‘Obla~inska’, ‘Ciganymeggy’ sour cherry, 13 selections of P. fruticosa and two candidates of P. mahaleb. ‘Gisela 5’ and ‘Colt’ were used as control rootstocks. Compared to plants on ‘Gisela 5’, TCSA reduction was achieved in 41% of rootstock candidates, while 96% of candidates induced reduction compared to control trees on ‘Colt’. That indicated low-vigorous character of those rootstock candidates, with most candidates within the P. cerasus group (seven candidates) reducing TCSA to a higher extent than the dwarfing control, followed by four European ground cherry candidates. Regarding fruit characteristics, fruit mass was higher in 52% of the rootstock candidates than in the control trees (P < 0.05), with fruit mass under 8.5 g on both standard rootstocks. Nine rootstock candidates of P. cerasus and six candidates of P. fruticosa, had an average fruit mass was above 9 g. Fruit mass above 9.5 g was obtained on: ‘PC_06_04’ (9.95 g), ‘PC_06_07’ (9.91 g), ‘PF_05_06’ (9.88 g), ‘PF_06_04’ (10.54 g), ‘PF_06_06’ (9.82 g), ‘PF_07_01’ (9.59 g), ‘PF_07_02’ (10.2 g) and ‘PM_09_02’ (10.32 g). When grafted on 12 rootstock candidates, fruits of the cultivar ‘Summit’ were characterized with fruit width above 27 mm, while three scion-rootstock combinations achived average fruit width higher than 28 mm: ‘PF_05_06’ (28.01 mm), ‘PF_06_04’ (28.11 mm) and ‘PF_07_02’ (28.2 mm). Soluble solids content ranged from 14.82% on ‘PF_06_08’ and 14.9% on ‘PM_09_02’ to 19.02% on ‘PC_06_12’, with 25 candidate rootstocks having soluble solids content greater than 15% - four candidates induced higher soluble solids content compared to controls. In addition to the candidate ‘PC_06_12’, the soluble solids content above 16% was achieved on ‘PC_01_01’, ‘PC_02_01/4’, ‘PC_03_02’, ‘PC_03_03’, ‘PC_04_01’, ‘PC_05_04’, ‘PC_06_04’, ‘PF_02_16’, ‘PF_06_06’, ‘PF_07_01’, ‘PF_07_02’, ‘PF_07_05’ and ‘PM_09_01’. The results showed that within ‘Oblačinska’ sour cherry and European ground cherry germplasm, some rootstock candidates have the potential to be used as low-vigorous rootstocks which induce high fruit quality of grafted cultivars. Among the many perspective rootstock candidates, ‘PC_06_04’ and ‘PF_07_02’ stood out in terms of the positive influence on the most important fruit traits - mass, width, and soluble solids content, and in terms of reducing vegetative growth of grafted sweet cherry trees.

Key words: Prunus cerasus L., Prunus fruticosa Pall., Prunus mahaleb L., rootstocks, sweet cherry, vigour, fruit quality

Title: FLORISTIC ANALYSIS OF WEEDS IN RASPBERRY PLANTATIONS UNDER ORGANIC PRODUCTION

Authors:Sanja Živković, Tanja Vasić, Darko Jevremović, Vera Katanić, Olga Mitrović, Bojana Vasilijević, Mitra Debasis

Download: PDF

Abstract: The analysis of the weed flora in the young raspberry plantations in the village of Osreci revealed the presence of a total of 26 weed species [7 weed (segetal), 13 weed-ruderal, 1 ruderal and 5 weeds of meadows and pastures]. The most of the identified weeds flowered from June to September. The recorded weed flora is dominated by representatives of the class Magnoliopsida (dicotyledons, broad-leaved weeds) with 24 species, while only two species are present from the class Liliopsida (monocotyledons, narrow-leaved weeds). The analysis of weed life forms in raspberry plantations shows a slight dominance of hemicryptophytes (38.46%) compared to geophytes (30.77%) and therophytes (26.92%). The number of weeds was not high, because inter-row cultivation was done every ten to fifteen days, and weeds were manually removed in the rows, around the plants. Regardless of the mechanical removal of weeds, the diversity of the weed flora was not negligible. In all observed young raspberry plantations, the most frequent weeds are: Salvia verticillata L., Lathyrus latifolius L., Cirsium arvense (L.) Scop., Equisetum arvense L., Pteridium aquilinum (L.) Kuhn., Polygonum convolvulus L., Convolvulus arvensis L., Chenopodium album L.

Key words: raspberry, weed flora, broad-leaved weeds, narrow-leaved weeds

Title: Cultivating organic American highbush blueberries with retorted beech charcoal (RBC)

Authors:Sanja Živković, Tanja Vasić, Biljana Mihajlović, Vera Katanić, Bojana Vasilijević, Darko Jevremović, Mitra Debasis

Download: PDF

Abstract: The research conducted in this study aimed to investigate the impact of retorted beech charcoal on the shoot number and length of the highbush blueberry cultivar ‘Duke’. The experimental trial was established using randomized block system, consisting of three treatments and a control group. The control plants were potted in plastic containers filled with a mixture of sawdust and a substrate designed for commercial blueberry growing by Klasman. The plants in the treatment groups were potted similarly but with the addition of retorted beech charcoal in the root zone and around the root neck. Three different quantities of charcoal were used: 150 g (T1), 100 g (T2) and 50 g (T3). The number and length of shoots were monitored over the two-year period. The results indicated a positive influence of retorted beech charcoal on the number and length of shoots. Specifically, the plants in the treatment groups exhibited longer and more numerous shoots compared to the control group. Furthermore, the results varied depending on the quantity of retorted beech charcoal applied. The treatment with 150 g of retorted beech charcoal recorded the highest average length and number of shoots. Additionally, in both the treatment and control groups, a greater number and length of shoots were observed in the second year of the study.

Key words: organic plants growing, retort beech charcoal, highbush blueberry, vegetative growth